<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>画圆</title>
		<script type="text/javascript">

		var canvas=document.getElementById("canvas");
		 var cxt=canvas.getContext("2d");
		 //画一个空心圆
		cxt.beginPath();
		 cxt.arc(200,200,50,0,360,false);
		 cxt.lineWidth=5;
		 cxt.strokeStyle="red";
		 cxt.stroke();//画空心圆
		cxt.closePath();
		
		</script>
	</head>
	<body>
		<canvas id="canvas" ></canvas>
	</body>
</html>
